Xray – How Moka – Espresso Stove Pot Works ?

In this video you will see X-ray like footage of the Moka – Espresso Stove Pot combined with sound and video footage from my own Espresso stove pot.

The footage was made with neutron images that shows the coffe making process. The movie was made by A. Kaestner, Neutron imaging and activation group, Paul Scherrer Institut, Switzerland. The cold neutron imaging beam line ICON was used. The movie is four times faster than in real time.

Neutron imaging

Neutron imaging is the process of making an image with neutrons. The resulting image is based on the neutron attenuation properties of the imaged object. The resulting images have much in common with industrial X-ray images, but since the image is based on neutron attenuating properties instead of X-ray attenuation properties, some things easily visible with neutron imaging may be very challenging or impossible to see with X-ray imaging techniques (and vice versa).

Why the metal are transparent while the plastic of the grip is totally opaque

The reason lies in the interaction mechanism between neutrons and matter. The attenuation is determined by the configuration of neutrons and protons in the nucleus, this is very different compared to X-ray which are sensitive to the electron density of the elements. For neutrons this has the effect that even isotopes of the same element can have very different attenuation coefficients. In this specific case, hydrogen (water and plastic) have a higher attenuation than many metals (Aluminum for example is one of the most transparent elements for neutrons).